1. A light splash.
2. The sound of a light splash.
v. plashed, plash·ing, plash·es
To spatter (liquid) about; splash.
To cause a light splash.
[Possibly from Middle English plashe, pool of water, from Old English plæsc.]
I came upon this word in a children's book, written in the 50s and set in the 20s. This is the first I knew that there are light splashes and heavy splashes.